This invention relates to a die assembly for the cold drawing of wire and/or bar stock.
In wire drawing processes, it is common practice continuously to draw the wire stock through a die assembly which includes a pressure die followed by a drawing die which performs the sizing operation on the wire. Lubricant for the drawing die may be forced under pressure into a pressure chamber defined between the respective dies.
In assemblies of the above kind, the die nibs usually are cold pressed, heat shrunk or brazed into respective metal casings with an interference fit. Each die is then accurately sized to a required internal diameter. The casings are themselves held in a die box.
When a die becomes worn, it is resized by machining to a larger internal diameter and the die can then be reused for wire stock of a larger diameter. Clearly, resizing can only be repeated a limited number of times for each die assembly, which is then discarded.